add alert to logmania

cmd/logmania/main.go

@@ -59,6 +59,8 @@ func main() {
 		}
 	}()
 
+	go notifyState.Alert(config.Notify.AlertCheck.Duration, log.Save)
+
 	log.Info("starting logmania")
 
 	receiver = allReceiver.Init(&config.Receive, logChannel)

lib/config.go

@@ -16,8 +16,9 @@ type Config struct {
 }
 
 type NotifyConfig struct {
-	StateFile string `toml:"state_file"`
-	XMPP      struct {
+	StateFile  string   `toml:"state_file"`
+	AlertCheck Duration `toml:"alert_check"`
+	XMPP       struct {
 		Host          string `toml:"host"`
 		Username      string `toml:"username"`
 		Password      string `toml:"password"`

lib/duration.go

@@ -0,0 +1,56 @@
+package lib
+
+import (
+	"fmt"
+	"strconv"
+	"time"
+)
+
+// Duration is a TOML datatype
+// A duration string is a possibly signed sequence of
+// decimal numbers  and a unit suffix,
+// such as "300s", "1.5h" or "5d".
+// Valid time units are "s", "m", "h", "d", "w".
+type Duration struct {
+	time.Duration
+}
+
+// UnmarshalTOML parses a duration string.
+func (d *Duration) UnmarshalTOML(dataInterface interface{}) error {
+	var data string
+	switch dataInterface.(type) {
+	case string:
+		data = dataInterface.(string)
+	default:
+		return fmt.Errorf("invalid duration: \"%s\"", dataInterface)
+	}
+	// " + int + unit + "
+	if len(data) < 2 {
+		return fmt.Errorf("invalid duration: \"%s\"", data)
+	}
+
+	unit := data[len(data)-1]
+	value, err := strconv.Atoi(string(data[:len(data)-1]))
+	if err != nil {
+		return fmt.Errorf("unable to parse duration %s: %s", data, err)
+	}
+
+	switch unit {
+	case 's':
+		d.Duration = time.Duration(value) * time.Second
+	case 'm':
+		d.Duration = time.Duration(value) * time.Minute
+	case 'h':
+		d.Duration = time.Duration(value) * time.Hour
+	case 'd':
+		d.Duration = time.Duration(value) * time.Hour * 24
+	case 'w':
+		d.Duration = time.Duration(value) * time.Hour * 24 * 7
+	case 'y':
+		d.Duration = time.Duration(value) * time.Hour * 24 * 365
+	default:
+		return fmt.Errorf("invalid duration unit: %s", string(unit))
+	}
+
+	return nil
+}

lib/duration_test.go

@@ -0,0 +1,47 @@
+package lib
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDuration(t *testing.T) {
+	assert := assert.New(t)
+
+	var tests = []struct {
+		input    string
+		err      string
+		duration time.Duration
+	}{
+		{"", "invalid duration: \"\"", 0},
+		{"1x", "invalid duration unit: x", 0},
+		{"1s", "", time.Second},
+		{"73s", "", time.Second * 73},
+		{"1m", "", time.Minute},
+		{"73m", "", time.Minute * 73},
+		{"1h", "", time.Hour},
+		{"43h", "", time.Hour * 43},
+		{"1d", "", time.Hour * 24},
+		{"8d", "", time.Hour * 24 * 8},
+		{"1w", "", time.Hour * 24 * 7},
+		{"52w", "", time.Hour * 24 * 7 * 52},
+		{"1y", "", time.Hour * 24 * 365},
+		{"3y", "", time.Hour * 24 * 365 * 3},
+	}
+
+	for _, test := range tests {
+
+		d := Duration{}
+		err := d.UnmarshalTOML(test.input)
+		duration := d.Duration
+
+		if test.err == "" {
+			assert.NoError(err)
+			assert.Equal(test.duration, duration)
+		} else {
+			assert.EqualError(err, test.err)
+		}
+	}
+}

notify/config/config.go

@@ -10,18 +10,22 @@ import (
 	"github.com/genofire/logmania/log"
 )
 
+const AlertMsg = "alert service from logmania, device did not send new message for a while"
+
 type NotifyState struct {
 	Hostname       map[string]string                    `json:"hostname"`
 	HostTo         map[string]map[string]bool           `json:"host_to"`
 	MaxPrioIn      map[string]log.LogLevel              `json:"maxLevel"`
 	RegexIn        map[string]map[string]*regexp.Regexp `json:"regexIn"`
 	Lastseen       map[string]time.Time                 `json:"lastseen,omitempty"`
-	LastseenNotify map[string]time.Time                 `json:"lastseen_notify,omitempty"`
+	LastseenNotify map[string]time.Time                 `json:"-"`
 }
 
 func (state *NotifyState) SendTo(e *log.Entry) []string {
 	if to, ok := state.HostTo[e.Hostname]; ok {
-		state.Lastseen[e.Hostname] = time.Now()
+		if e.Text != AlertMsg && e.Hostname != "" {
+			state.Lastseen[e.Hostname] = time.Now()
+		}
 		var toList []string
 		for toEntry, _ := range to {
 			if lvl := state.MaxPrioIn[toEntry]; e.Level < lvl {
@@ -108,6 +112,26 @@ func (state *NotifyState) Saver(path string) {
 	}
 }
 
+func (state *NotifyState) Alert(expired time.Duration, send func(e *log.Entry)) {
+	c := time.Tick(time.Minute)
+
+	for range c {
+		now := time.Now()
+		for host, time := range state.Lastseen {
+			if time.Before(now.Add(expired * -2)) {
+				if timeNotify, ok := state.LastseenNotify[host]; !ok || !time.Before(timeNotify) {
+					state.LastseenNotify[host] = now
+					send(&log.Entry{
+						Hostname: host,
+						Level:    log.ErrorLevel,
+						Text:     AlertMsg,
+					})
+				}
+			}
+		}
+	}
+}
+
 // SaveJSON to path
 func (state *NotifyState) SaveJSON(outputFile string) {
 	tmpFile := outputFile + ".tmp"